Query Posts with meta_query key in arrayYou would need to get all of the posts, then loop through the 'repeated_intervals' metadata to unserialize it and do your comparison on each date to make a list of posts that match your desired less than or equal to comparison.

Query Posts with meta_query key in arrayIf the 'repeated_intervals' metadata is stored as a serialized array, you won't be able to do a meta_query - you are trying to compare one date with an array of dates ( if I understand this question correctly ).

Page with children of different post typescore.trac.wordpress.org/ticket/18962 This is to prevent 'structure_parent/cpt' from a custom post type from clashing with the hierarchical page 'structure_parent/cpt'. However, what you are seeking to do seems like a poor information architecture - mixing custom post types with pages under the same parent. What is the point of the custom post type? Why not just use pages w/ meta boxes if you need specific content?

Handling complex multi-level architecture / menu for large siteA section is made up of hierarchically structured pages, custom links, and random other posts ( from various post types ). Not a great IA structure, but a legacy one we are working on fixing - slowly. Again, the actual form makes no difference - we can put / structure / style this in any way with native functions, queries, and css. What is still "wishy washy" exactly?